In the start-up phase, the main objective of HTExplore is to provide specialized HTE services for the fine-tuning and optimization of polyolefin catalysts and/or processes.

To better understand the background, it is important to recall that a typical catalyst system for olefin polymerization includes (a) a transition metal pre-catalyst; (b) a main group metal-alkyl, as alkylating agent and/or scavenger; (c) an activator (which in some cases coincides with b); and possibly (d, e, …) additional ‘ingredients’ (e.g., promoters, selective ‘traps’, selective modifiers, etc). The catalytic performance of this complex pool is crucially dependent on the nature and amounts of the individual components, their cross-interactions (usually extensive, which implies that the choice of activation and reaction protocols can also be delicate and critical), and of course physical and chemical variables like temperature, pressure, solvent/diluent when used, etc. It is fairly common, in particular, that the productivity of a given catalyst changes by orders of magnitude depending on different choices of the aforementioned system constituents and variables. An extreme example are metallocene catalysts, disclosed in the late-1950s but considered of no practical interest for over 20 years, until the serendipitous discovery of methylaluminoxane (MAO) as an activator in the place of AlR3-xClx literally boosted activity. This is not an isolated case, though; as a matter of fact, most olefin polymerization catalysts perform well only within a fairly narrow operating window, and locating such a window requires intensive and systematic experimental work (or plenty of good luck…). It is in this respect that the availability and professional use of state-of-the-art HTE tools and methods can be decisive for success.

Based on experience, a thorough screening can take up to several hundred polymerization runs for each given pre-catalyst structure. With conventional tools, this can take months of a dedicated skilled operator (mostly bound to repetitive work), and large amounts of chemicals. Recent work at LSP, on the other hand, demonstrated (Busico, V.; Pellecchia, R.; Cutillo, F.; Cipullo, R. Macromol. Rapid Commun.2009, 30, 1697-1708) that with a state-of-the-art HTE platform for secondary screening like the Freeslate PPR48 the job can be completed in just a few days. Moreover, due to the miniaturization of the HTE reactors (with a working volume of only 5-6 mL), the consumption of chemicals is nominal, which leads to a substantial reduction of costs and wastes. Last but not least, data reproducibility is extremely high, as an inherent feature of robotic operation inside a glovebox environment.

The basic principles of the approach and case histories of successful application in heterogeneous and molecular catalysis were presented by Prof. Busico in a recent Freeslate-organized webinar.

On the other hand, a number of drawbacks hinder widespread diffusion. In particular:

i) State-of-the-art HTE workflows can be capital intensive

ii) To get the most value out of them, operators need to develop an adequate level of expertise on tools and methods

It is exactly to overcome the above drawbacks that HTExplore has been created; in fact, specific solutions are proposed for all of them, as can be learned at the ‘Services’ page.

Longer-Term Plans

Like for all advanced technologies, innovation in HTE is fast. What represents the state-of-the-art today becomes obsolete in a few years, and without adequate investments in new tools and methodologies it is impossible to maintain a competitive edge.

The most spectacular advances in recent times concerned the analytical tools for rapid polymer characterizations. In particular, NMR and fractionation instruments have become fast to the point that the rate limited step moved from data acquisition to sample preparation and/or data analysis. We are actively working on both aspects in order to speed-up operation and remove existing bottlenecks.

On the other hand, we realize that penetration of HTE tools and methods into routine chemical research practice is slow, particularly in academia. In our opinion, the main reason is that, even with the mediation of a company like ours, the classical HTE approach is complicated and expensive, particularly when the system(s) to investigate are poorly understood and a very large number of experiments are necessary to identify hits and from these proceed to leads on a purely hit-or-miss basis. Focusing the search by means of a QSAR model (either of black-box or clear-box type) can represent an effective solution, but requires a significant know-how. In particular, the process of model implementation, validation and benchmarking is demanding in terms of mathematical, statistical and computational skills. We aim to make this part more readily accessible as an additional service offered to our customers. Moreover, we are discussing with several hardware and software producers how to develop a new generation of integrated and more user-friendly HTE tools and methods for chemical discovery and optimization, with significantly lower capex and opex compared with present-day ones (see Newsletter of December 2015).

In general, at HTExplore we are interested to incubate new HTE technologies for organometallic catalyst screening and polymer characterizations. We are open to collaborations and joint ventures, as well as ‘venture technology’ projects in which new ideas can be explored on our HTE platforms (of course once proper secrecy agreements are set in place). Feel free to contact us and share your thoughts with us; we are always open to new challenging adventures!